Rotary drying apparatus



'Dec. .29 1925. 1,567,335

P. SCRIVE ROTARY DRYING APPARATUS Filed Jan. 12, 1924 P SCI/619% ymxew Patented Dec. 29, 1925.

1,561,335 PATENT OFFICE.

rim. SCRIVE, or rams, reason.

ROTARY DRYING APPARATUS.

Application filed January 12. 1924. Serial No. 685,855.

To all whom it may mm.-

Be it known that I, PAUL Semvn, a citizen of the French Republic, residing 1 Rue de la Reale, Paris, France, have invented new and useful Improvements in Rotary Drying Apparatus,flof which the following is the specification.

Rotary drying apparatus with inclined axes are .already known, having side walls in the shape of buckets and longitudinal openings between two adjacent buckets for the admission of the hot gases which are sucked by the axis) of the drum, which axis is hollow and perforated with radial holes. These drying apparatus are so constructed that the materials contained in a bucket are discharged, during the rotation of the drum, intothe following buckets; but it very frequently happens that the materials treated stick to the walls and that they come off at a time their fall carries them outside the drum through the longitudinal openings of the latter.

' This inconvenience would be rendered still more serious in case it should be desired to introduce the hot gases in the drum through the hollow perforated axis, these v gases being evacuated through the longitudinalopenings. In fact, in this case, it is obvious that the gases, by escaping through the side openings of the drum, would still facilitate the issue of a portion of the materials from the drum.

- hot gases under way of example only, a form of carrying out this invention.

The improvement forming the subjectmatter of the presentinvention is adapted to do away with this inconvenience and to thus permit, if desired, the introduction of tral hollow shaft.

The accompanying drawing illustrates, by

Fig. 1 is a cross-section of the drum.

Fig. 2 is a partial sectional elevation.

In this example, the drying drum is-essen tially contituted by groups of longitudinally arranged sheet-iron plates 1 and 2; in each group L 2, the sheet-iron plates have a common edge, at 3, so as to form, in cross section,

a more or less open V. The edges 3 are so arranged as to constitute the edges of a regular prismatic surface, a hexagonal surface v,in the exgrnple illustrated. The 'im rove-' ment fvention cpnsists in arranging on the inner face of the walls. 2, and at their end 4, a

ithesubject-matter of t e inpressure through the cen sheet-iron plate 5 which connects them to the walls 1.

These perforations are provided only on the zone 67, that is to say preferabl on about half the width of the sheet-iron p ates. Another sheet iron edge 9 of which is in the edge 3 to the line 7.

The admission of the materials takes place through the spout 10; a fixed obturating plate 11 is rigid with this spout and the shaft '12 passes through this plate 11. On the other hand, the drum carries at its end an annular closing sheet iron plate 13, the edges of which slightly extendbeyond those of the circular fixed'plate 11'. In this manner, the materials cannot escape through the end of the drum. V

The hot gases enter the drum thus constituted through openings which exist between the edge 4 and the adjacent sheet-iron plate 1 ,the hot gases being first in contact with the most moist materials, near the charging end of the rotating drum.

The materials received in each of the Vs plane joining the constituted by the sheet-iron plates 1 -2 are materials which originally were the nearest the overflowing edge are, when reaching the following sheet-iron plate, the farthest from the overflowing edge limiting the latter. Consequently, at each stage of overflowing, the materials which were the less ventilate are, on the contrary, subjected to the most considerable ventilation, action of displacement to which is added that resulting from the fall of the materials in the stream of hot gases. Allthese arrangements are already known.

But, it-happens that agglutinated mate; rials stick tot e bottom 0 the V formed by the sheet-iron plates 1 and 2; when these materials come off once the V has passed the plate 8 is provided, th c,v

The sheet-iron plates 5 are perforated with holes of small diameter.

vertical, the materials which are not stopped by the sheet iron plate 8 can fall on the sheet iron plate 5 only in the non-perforated zone 74 and fall again in the V when the latter arrives to its lower position. In the same way, the materials collected by the sheet iron plate 8 also fall again at this moment in the V.

In the example illustrated, use is made of sheet-iron plates l4, preferably plane, so that the materials which remain attached *to the projecting parts 15 'fall back upon by the hot gases, have, moreover, for effeet to increase the useful surface of the apparatus and, consequently, its efficiency and capacity of utilization.

Of course, the projecting parts 15 can be provided in any number and the various sheet-iron plates can have any shape. It will also be understood that the multiplicity of the screens of materials freely falling down, screens through which pass the hot gases, ensures afbettef utilisation of these gases, the passage of Which in the apparatus lasts a longer time owing to a more sinuous path:

What I claim as my invention and desire to secure by Letters Patent is:

1. In a rotary drying apparatus having aninclined axis for pulverulent materials, a drum constituted by the assemblage of several longitudinal buckets, the concavities of which are turned inwardly, the said buckets being arranged in a geometrically similar manner relatively to the axis of the drum, and providing between them'equa-l intervals, longitudinal plates obturating the saidintervals, these plates being. perforated on a portion of their width.

2. In a rotary drying apparatus having an inclined axis for pulverulent materials, a drum constituted by the assemblage of several longitudinal buckets, the concavities of which are turned inwardly, the said buckets beingarranged in a geometrically similar manner relatively to the axis of the drum, and providing between them equal intervals, longitudinal plates obturating the said intervals these plates being perforated on a portion of their width, other plates arranged for protecting these perforated portions.

3. In a rotary drying apparatus having an inclined axis for pulverulent materials, a drum constituted by the assemblage of several longitudinal buckets, the concavities of which are turned inwardly, the said buckets being arranged in a geometrically similar manner relatively to the axis of the drum, and providing between them equal intervals, buckets each constituted by two sheet-iron plates forming a dihedral angle, the arrangen'ient of these buckets so that the apex of each dihedral angle coincides with the ed o'of ii -prismatic surface having for straight section a regular polygon, longitudinal plates obturating the intervals provided between the buckets, these plates being perforated on a portion of their Width, other plates arranged for protecting the perforated portions, and extending up to a plane connecting the apex of the dihedral angle to the limit of the perforated portion.

In testimony whereof I' have signed my name to this specification.

PAUL SCRIVE. 

